1. Field of the Invention
The present invention relates to devices and methods that allow for data to be transferred while preserving integrity of that data. The present invention further relates to a technique for acquiring and multiplexing together different signal types, wherein that technique is used for instrumentation recorders or for delivering the signals across a communications link. The signals can be multiplexed together and written onto magnetic media, compact disk, or similar archiving mechanisms or sent to another module through the communications link. Thereafter, the signals can be reconstructed, either from the stored signals or after being retrieved after being sent across a network, while maintaining the fidelity and phase relationships of the original signals
2. Description of Related Art
There are many processes in data acquisition and processing that require obtaining, processing and transferring data. As an example, if video and audio data are obtained through a camera apparatus and it is desirous that the audio and video data be transferred for viewing at a distant location, the audio and video is often combined and then transferred over a network. When the signals are combined, it is important for the relationships between the signals to be maintained so that the signals can be coherently displayed or evaluated at the destination.
There are a number of prior art methods that utilize multiplexing techniques and formats with tape recorders that are standardized. Many of these prior art techniques involve taking in different signal types, perhaps all in a digital format or analog signals that are going to be digitized through some sort of sampling technique. It is important that enough information be captured so that the signals may be reconstructed with some fidelity. With an analog signal, some of the issues are how rapidly the data are sampled in a phase/frequency context, how many bits are used to represent the changes in amplitude in the dynamic range, etc. However, these techniques do not usually maintain the phase relationships between the signals in addition to the fidelity of the signals and they do not automatically adapt to changes in the data rate of the input channels.
There are ways to adapt to changes in signal data rates and to maintain the phase relationships between the signals, and when the prior art methods do address rate adaptation and the maintenance of phase relationships, these methods result in the multiplexed data having formats that have fairly high overheads. In a multiplexer, there is a certain bandwidth of signals coming in, in terms of the frequency content of the analog signal or the clocking rate of the digital signal and then there's an information rate of the digital stream coming out. The overhead is the difference between the output information rate and the sum of the input information rates. Existing techniques that maintain the phase relationships between the signals result in high overheads in that they output a lot of data either to the tape or to the network regardless of how much data is actually being received
As such, there is a need for a method or mechanism that can provide for maintaining the information necessary to reconstruct the signals accurately, such that they maintain the same base relationship to one another. In addition, there is also a need for a system and method that maintains the phase relationships between the signals in a way that provides a lower overhead, meaning that the amount of data sent is only a small percentage greater than what is actually coming in.